The blend of oils – also including coriander, neroli and cinnamon oils – and alcohol is reported to be the formula for the so-called “Merchandise 7X”, which gives the famed soft drink its distinctive flavour.

The blog has also included a recipe published in a book in the 1990s, which is similar to the 1979 version, but calls for four times as much of each of the oils.

The soft drink was created in 1886 by pharmacist John Pemberton in Atlanta, Georgia, and the recipe has always been kept under wraps.

Legend has it that the exact details of the recipe are kept locked in a bank vault in Atlanta.